...and I've found out that the last number represents the year the piece was made, thus HG4 means it was made in 1974. As far as I can tell this was used between 1972-79.

I have one piece from 1980 signed "HG80", but it seems that the system of signature became quite random in the 80s/90s - sometimes using a date code, sometimes a pattern number, sometimes a full date. I'll eventually sort through it, I'm sure.

I am not sure that you are right on that point. A lot of items has not been signatured, as I understand it, it was only done when the time was to it, and therefore a lot of Holmegaard production has no signature.

The signature you refer to, is mostly found on drinking glass and offcouse the HG stands for Holmegaard but the number most likely refer to the number off glass i a series, beer HG1, redwine HG2, whitewin, HG3 and so on, but only in that glass series. If you have Shipsglass redwine with HG2 it do not means that Tivoli redwine also have HG2 it can be a differet cifer.

If we are talking signature on vases, bowls ect. they may be with signature HOLMEGAARD 15768, where number is stock item number, this number can later on be another number, due to chance in stock program, although it is the same item it could be with a signature like HOLMEGAARD 2001234.

The there is all the designer signature often like HOLMEGAARD 19PL76 or HOLMEGAARD MB80 and so on, the most found signature is:

I gleaned the information I stated from the folk at Glashistorisk Selskab Holbæk, and it seems to hold true for vases, decanters and bowls, at least. I'm not sure about drinking glasses - it's something I'll have to look into further.

Except for expensive limited edition pieces, it seems that Holmegaard stopped fully signing with stock numbers around 1970, and went to the HG+number format. It wasn't just on drinking glasses. Some of the 5-digit stock numbers did change over time, but most of them stayed the same throughout the pattern's lifespan. The catalogue numbers changed in 1965 to a 6-digit number, but these seem to be independent of the stock number, so number 15768 might have stayed the same, even if its Kastrup-Holmegaard catalogue number became 20 012 34.

I've never seen a Jacob Bang signature on glass (except for the press-moulded monograms on hte Capri and Antikgrøn series) - do you have any images of his etched signature?

We bought it together with an opaline decanter and glasses from Denmark about 3 years ago, the seller made no mention that it was marked, so I'm sure they had'nt spotted it (not that easy to see on the white) I think the last mark is an 'x' but suppose it could be read as a 'k' for Kastrup??

On HG the dates usually refer to production rather than design dont they, making this the same year as it was designed.

Have just gone into the holmgaard resources site to try and date a production number I have on a Per Lutken vase-no sucess but did fine a qualification on a decanter I have-Per Lutken!! What a suprise. The number in question is 220194-can anyone of you lovely people help. Many thanks to pinkspoons for what appears to be a labour of love-excellent site even though it is in developement. regards from New Zealand